Poinsettia plant named `Nobelstar`

ABSTRACT

A distinct cultivar of poinsettia plant named Nobelstar, characterized by the combined traits of light coral red bract color, compact and well branched plant habit, medium green foliage, broad elliptically shaped bracts, and medium early flowering repsonse.

The present invention relates to a new and distinct cultivar ofpoinsettia plant, botanically known as Euphorbia pulcherrima, and knownby the cultivar name Nobelstar.

The new cultivar Nobelstar is a naturally occurring spontaneous mutationof Peterstar, disclosed in U.S. Plant Pat. No. 8,259, characterized byits bright red bract color, medium green foliage, comparatively compactplant habit, medium early response in autumn, and good branchingability.

The new cultivar was discovered by the inventor Eva Dahlqvist-Olsson asa mutation among a group of stock plants of the parent cultivarPeterstar growing in a greenhouse in Malmoe, Sweden in Autumn 1992. Onebranch of the plant displayed bracts having a substantially lighter,coral red color compared to the bright red bract color of the parent.Shoots developing from the mutated branch were severed by the inventor,planted as cuttings, and grown out. Plants grown our were asexuallypropagated by the inventor in Malmoe, Sweden in order to obtain a clonewith stable and uniform characteristics. Successive generations ofasexually reproduced clones were observed to be stable and to relaiblyexpress the distinguishing characteristics of the initially discoveredsport.

The following traits have been repeatedly observed and are determined tobe basic characteristics of Nobelstar which in combination distinguishthis poinsettia as a new and distinct cultivar:

1. Light coral red bract color.

2. Compact and well branched plant habit.

3. Medium green foliage.

4. Medium early flowering response.

5. Broad, elliptically shaped bracts.

Nobelstar has not been observed under all possible environmentalconditions. The phenotype may vary significantly with variations inenvironment such as temperature, light intensity, and daylength without,however, any variance in genotype. The following observations,measurements and comparisons describe plants grown in Hillscheid,Germany, under greenhouse conditions which approximate those generallyused in commerical practice.

Of the many commercial cultivars known to the inventor, the most similarin comparison to Nobelstar is the parent cultivar Peterstar. Nobelstarhas a light coral red bract color compared to the bright red bract colorof Peterstar, and Nobelstar has displayed a somewhat more compact growthhabit, reaching a typical plant height of 22 cm, compared to 25 cm ofPeterstar, when plants are grown under the same conditions. Nobelstarcan also be compared to the cultivar Fisbon, disclosed in pendingapplication Ser. No. 08/327,929. Both cultivars have similar growthhabit and plant height. The bract colors are distinctly different, withNobelstar having a unique bright light red broad color and Fisbon a moreorange-red bract color. In addition, the leaf petioles of Nobelstar arehigher than in Fisbon due to less intense anthocyanin coloring, and thereddish color of the styles and top part of the cyathia are lighter inNobelstar than in Fisbon.

The accompanying color photographic drawing shows typical inflorescenceand foliage of a potted plant of Nobelstar, with colors being as true aspossible with illustrations of this type.

In the following description, color references are made to The RoyalHorticultural Society Colour Chart. The color values were determinedindoors in Hillscheid, Germany (latitude 50° N). They were planted asrooted cuttings into 14 cm pots in early June, potted in late June andpinched 14 days later. Plants were grown under dark cloth (short daytreatment) from July 25. These plants and those of the comparisoncultivar Peterstar were treated with growth regulator Cyocel threetimes. The last treatment was six weeks before the observation date.Observations and measurements were taken at the beginning of floweringin mid-September.

Classification:

Botanical.--Euphorbia pulcherrima.

Commerical.--Poinsettia, cv. Nobelstar.

Parentage: A naturally occurring mutation from the cultivar Peterstar.

Plant description:

Form.--Broad, bushy, 6-7 branches.

Growth habit.--Compact growth habit; height approximately 22 cm.

Rooting.--Fast; less than 20 days.

Blooming season.--From late November (about 9 weeks of response time).

Blooming habit.--Saleable from late November, when 3-6 bracts arecompletely colored.

Foliage.--Size: Leaf is approximately 13 cm in length; petiole is 6-7 cmin length. Internodes: 15-20 mm. Color: Mature foliage: Upper surface137A; under surface 137C. Leaf petiole: Light red. Shape: Ellipticalwith weak lobes, rounded base. Texture: Upper side, slightly rugose;lower side, weak veins. Edge of margin: Entire. Disease resistance: Nounusual susceptibilities to common poinsettia diseases have been notedto date.

Flowering description:

Cyathias.--Borne: In a narrow cluster. Quantity: 14-14. Retention: Good.

Bracts.--Elliptical, folded along the midrib, surface rugose; largestcolored bract with petiole is 16 cm long.

Color.--Upper surface 44C; lower surface 46D. By comparison the uppersurface bract color of Peterstar is bright red 45B.

Reproductive organs:

Glands, nectar cups.--Orange-yellow.

Stamens.--Light red turning to brown, hardly any fertile stamens.

Pollen.--Very little, yellow in color.

Styles.--Light red, 6-lobed stigma.

Ovaries.--Triangular, 3-celled, 3 ovules.

I claim:
 1. A new and distinct poinsettia plant named Nobelstar, asillustrated and described.